Shimano Tourney TX RD-TX800 8/7-speed MTB rear derailleur ERDTX800SGSL

A derailleur Shimano A reliable and versatile Tourney TX for 7- and 8-speed drivetrains

The Shimano Tourney TX RD-TX800 SGS is a mountain bike rear derailleur designed for drivetrains 7- and 8-speed. Reference ERDTX800SGSL, this model at SGS long screed offers a total capacity of 43 teeth and is compatible with a cassette or a freewheel with a large sprocket up to 34 teeth.

Thanks to its mechanism Double Servo-Panta, the RD-TX800 offers smooth operation and precise gear changes. Shimano It is designed specifically for mountain bikes and leisure bikes fitted with a 7- or 8-speed SIS mechanical gear system.

Its design prioritises the simplicity, robustness and ease of adjustment, making it a particularly suitable solution for replacing a worn derailleur or refurbishing a bike fitted with a drivetrain Shimano 7/8 speeds.

Shimano Tourney TX RD-TX800: a simple and efficient 7/8-speed drivetrain

The Tourney TX comprises a range Shimano designed in particular for leisure bikes and entry-level mountain bikes.

The RD-TX800 is compatible with TV channels Shimano HG 8/7/6-speed and features a mechanical indexed gear-change system. Shimano promises a smooth ride and a gearbox designed to deliver reliable gear changes for everyday use.

It is therefore a suitable choice for replacing an old rear derailleur on a mountain bike, a trekking bike or a versatile bike fitted with a compatible 7- or 8-speed drivetrain.

Chape Long SGS: up to 34 teeth

The version SGS features a long shank, allowing it to accommodate a relatively wide range of thread pitches.

The RD-TX800 supports:

• a small cogwheel 11 to 14 teeth ; ;
• a large sprocket 28 to 34 teeth ; ;
• a maximum difference between plates of 20 teeth ; ;
• a maximum total capacity of 43 teeth.

This configuration allows it to be used with a wide range of MTB and trekking drivetrains featuring 2 or 3 chainrings, provided that the derailleur’s maximum capacity is not exceeded.

Example of a compatible configuration

With a three-chainring drivetrain, the total capacity is calculated by adding:

the difference between the large and small chainrings + the difference between the largest and smallest sprockets.

It is therefore important to check this capacity before assembly.

Double Servo-Panta mechanism

The Double Servo-Panta is one of the characteristics of the Shimano Tourney TX RD-TX800.

This mechanism follows the movement of the derailleur to maintain the correct position relative to the cassette whilst changing gears. Shimano highlights this approach in order to achieve a smooth and sustained gear-changing action.

Whether for a bike intended for everyday commuting, leisure or mountain biking, this design prioritises simplicity and reliability above all else.

13/13-tooth sprockets

The RD-TX800 is fitted with two rollers 13 teeth, with an upper and a lower roller of the same size.

This design contributes to the smooth operation of the line and the effective management of the SGS long-strip screed’s capacity.

Conventional derailleur hanger mounting

The RD-TX800 ERDTX800SGSL It is mounted on a conventional MTB-style rear derailleur hanger, with the derailleur attached directly to the hanger.

This is not a model Direct Mount neither a modern derailleur nor one compatible with the UDH standard. Shimano indicates a standard MTB-type mounting.

Before placing an order, it is therefore advisable to check the mounting system on the frame.

Technical specifications

Technical data sourced from Shimano and the documentation relating to product reference ERDTX800SGSL.

Compatibility

The Shimano RD-TX800 SGS is intended for transmissions Shimano 7- and 8-speed using a SIS-compatible mechanical gear-changing system.

It is particularly suitable for the following set-ups:

• 7-speed mountain bike ;
• 8-speed mountain bike ;
• 7- or 8-speed trekking bikes ;
• leisure bikes ;
• city bikes fitted with a gearbox Shimano compatible ;
• 2- or 3-chainring drivetrains, subject to the derailleur’s capacity.

Check for compatibility

The number of gears alone is not enough to guarantee compatibility.

You should also check:

1. the type of derailleur mounting ;
2. the number of rear gears ;
3. the compatibility of the gear lever ;
4. the total capacity of the transmission ;
5. the size of the largest sprocket.

The RD-TX800 accommodates a large sprocket up to 34 teeth and has a total capacity of 43 teeth.

The key features of the Shimano Tourney TX RD-TX800

• Compatible with 7- and 8-speed systems
• Chape long SGS
• Large sprocket up to 34 teeth
• Total capacity of 43 teeth
• Mechanism Double Servo-Panta
• Pebbles 13/13T
• Integrated cable adjustment
• Standard MTB binding
• Simple and robust design
• Ideal for repairing or refurbishing a mountain bike
• Precise reference ERDTX800SGSL
• Colour: black